I need to upgrade my regulator to minimize the risk of free flow in very cold (fresh) water. I have a Conshelf/Sea first stage for which I can have an environmental seal added. One local expert suggested that regulator technology hasn't really advanced much over the past 30 years, so the best solution for the second stage would be to get an old metal US Diver one. These are supposed to have superior heat sink characteristics compared to modern second stages.

Someone else said I should stay away from old metal second stages - they are hard to find parts for, have no Venturi adjustment, and are just not as nice to breathe from as newer equipment. He said I should make sure to get a balanced second stage with heat sink features.

I need to upgrade my regulator to minimize the risk of free flow in very cold (fresh) water. I have a Conshelf/Sea first stage for which I can have an environmental seal added. One local expert suggested that regulator technology hasn't really advanced much over the past 30 years, so the best solution for the second stage would be to get an old metal US Diver one. These are supposed to have superior heat sink characteristics compared to modern second stages.

Someone else said I should stay away from old metal second stages - they are hard to find parts for, have no Venturi adjustment, and are just not as nice to breathe from as newer equipment. He said I should make sure to get a balanced second stage with heat sink features.

Does anyone have an opinion on this question?

John McCracken

A Diver Once Said "A bad dive is always better than a good day at work!"

I'm trying to make the most of what I already own. I was told that adding an environmental seal to my Cousteau (Sea) first stage would make it functionally equivalent to the first stage of an Aqualung Legend LX Supreme, which has been given good reviews as a cold water regulator. If an old metal second stage resists freezing, as well as or better than a modern cold water second stage, then maybe I can have a good cold water regulator without having to spend much. Is that likely; or do I need to cough up the dough to get a regulator that is safe and a good performer in cold conditions (by anyone's standards)?

In general, I'm wondering if design changes over the past few decades have given us regulators that work better in cold water. If so, which new features are worth paying for? Would we be better off with metal second stages?

What's happening is that engraving is occurring between the valve seat and the poppet during storage. Get an Atomic. When it's not under pressure these two parts sit apart and engraving doesn't happen.

This is a good point, John,

The seat and poppet can be set apart on nearly all ScubaPro regs as well, but the oldest second stages.

I had many hours breathing from Russian up stream second stages, two hoses AVM 1M and Russian re-breathers. All of them served me well, without a single problem.

The key point is to service your regs when they need to.

I have tried all Scubapro second stages and my favorite one is the all metal Balanced Adjustable, made from 1969 till the late 90s. I can take it apart with closed eyes and put it back together.

I would suggest that for really cold water diving, you might want to look into a full face mask. I use the Interspiro (aka AGA) Divator II, and really like it, but there are others as well. They are very resistant to cold free flowing, and protect your face from the cold water as well, so you are much more comfortable for long periods of time in cold water.

HOG, dive them for a couple of years then bin them on ebay and pick up another set for less than it costs to service a set of Apeks or ScubaPro

They breath the same as the Apex.

Another for Apex or HOGs. As longer as they are environmentally sealed you are good. There is virtually no discernible difference between the WOB between low end and top end regs, so I would go for the base level everytime.

HOG services kits are readily available and cost $20 a pop so you can service yourself and save bucks